@slothlover888 I am not actually sure I understand what you have done so far, sorry 🙂
So I will try to recap:
Since you say that including CC in the search in the Gallery, and if by personal you mean your Library tab in the gallery from within game; then my thought is that you have a faulty CC file in your user folder. This is why I wanted you to try in a new folder, and to follow the troubleshooting step of adding back your files one at a time, or little by little, or by the 50/50 method, to see when the issue appears, and so perhaps figure out if, and if so which, CC you need to update/discard.
Have you done this:
Rename The Sims 4 folder located in Documents>Electronic Arts
Started the game
Created a new save
Opened the gallery
Checked the box to include custom content
and your Gallery Library in-game freezes; then it would help if you post info on your computer. Here is how:
https://help.ea.com/en/help/pc/how-to-gather-dxdiag-information/
If you have moved back all your files from your old The Sims 4 folder to the new one I think another reason for the gallery being slow, besides the files in the folder Mods; is if you have a lot of files in the Tray folder (also in The Sims 4 folder).
Then exit the game, and move them out (to for instance your Desktop for safe keeping) and delete the cache folder in the Sims 4 folder, and perhaps also the onlinethumbnailcache folder, and then try again. If the screen does not freeze then, you can try to only keep a number of files in the Tray folder, and store the others in a safe place until you want to use them.
Let me know if I should elaborate on anything.